CN109634276B

CN109634276B - Agricultural vehicle unmanned control method and system and agricultural vehicle

Info

Publication number: CN109634276B
Application number: CN201811525905.5A
Authority: CN
Inventors: 唐明; 姚谦礼; 丁捷; 周菁; 周欣
Original assignee: Zoomlion Heavy Industry Science and Technology Co Ltd
Current assignee: Zhonglian Agricultural Machinery Co., Ltd
Priority date: 2018-12-13
Filing date: 2018-12-13
Publication date: 2021-05-25
Anticipated expiration: 2038-12-13
Also published as: CN109634276A

Abstract

The invention relates to the field of agricultural machine automation, and discloses an agricultural vehicle unmanned control method and system and an agricultural vehicle. The unmanned control method for the agricultural vehicle comprises the following steps: acquiring closed farmland plot boundary data and discontinuous operation data acquired by a positioning system, wherein the discontinuous operation data comprises one or both of obstacle positioning data and non-operation area positioning data; acquiring vehicle steering angle data; and planning an unmanned automatic operation path according to the closed farmland plot boundary data, the discontinuous operation data and the vehicle steering angle data. The embodiment of the invention adopts a mode of combining a positioning technology and a tractor self steering angle acquisition technology to complete automatic path planning design, provides an obstacle avoidance strategy for obstacles and non-operation areas, and is a beneficial scheme with high efficiency, stability and cost saving.

Description

Agricultural vehicle unmanned control method and system and agricultural vehicle

Technical Field

The invention relates to the field of agricultural machine automation, in particular to an agricultural vehicle unmanned control method and system and an agricultural vehicle.

Background

With the implementation and promotion of 2025 strategy in China, the automation and intelligence level of agricultural machinery is continuously improved, and users put forward higher requirements on the automation degree of the agricultural machinery. In the field operation process of agricultural vehicles (hereinafter, tractors are taken as examples), operators often design field operation paths according to experience and some common knowledge rules, and problems of heavy plowing, missing plowing, multiple walking paths and the like exist, so that the operation production efficiency is influenced. Therefore, the automatic operation path planning and the agricultural implement control strategy design aiming at the unmanned system of the agricultural vehicle have great significance.

At present, the application of Global Navigation Satellite System (GNSS) technology represented by Global Positioning System (GPS) gradually meets the accuracy requirements of agricultural production on static positioning or dynamic positioning, and the GNSS technology can collect geographic information of a working area before working and reasonably plan a working path; in the operation process, the actions of steering, accelerating and decelerating, braking and the like of the tractor are controlled; and after the field operation is finished, the operation process and the operation effect are evaluated to accumulate the experience of the field operation. Therefore, the prior art provides a method for generating an optimal operation path covered by a farmland plot in a whole area based on a GPS technology, which provides the current operation position of a tractor in real time through a GPS positioning module, supports selection of various turning modes such as a semicircular mode, a pear mode and a fishtail mode according to the mechanical type and the operation requirement of an automatic tractor for an operation plot with a given shape, supports setting of various path optimization targets such as minimum turning, minimum turning operation consumption, shortest operation path, maximum effective operation path diameter ratio and the like, calculates and generates the optimal operation path covered by the farmland plot in the whole area according to different set turning modes and path optimization targets, and then enables a navigation module to realize automatic driving of a tractor unit according to the optimal operation path. However, this method has at least the following disadvantages:

1. the GPS technology is applied to automatic operation in agricultural production, and can realize high-precision static positioning or dynamic positioning, but a single GPS system is difficult to realize full-automatic operation of multiple operation lines, and cannot realize real unmanned driving due to the limitation of variability of a vehicle body angle in the steering process of a tractor.

2. The traditional steering modes such as the semicircular mode, the pear-shaped mode, the fishtail-shaped mode and the like can realize the whole-area coverage operation, but are mostly used for the sequential steering strategy between the traditional adjacent operation lines. Compared with the flexible and variable unequal number interlaced steering strategy, the steering modes are relatively time-consuming in operation, and the path required to be passed by each steering is relatively long. Meanwhile, the multiple steering modes are not beneficial to automatic control in the operation process, and difficulty is brought to automatic control of turning at the ground.

3. The commonly adopted sequence head-to-tail turning strategy between adjacent operation lines is more suitable for the regular operation area. For an irregular operation area, more turning points and different turning angles exist, and the conventional head-tail turning strategy cannot realize sequential head-tail turning between adjacent operation lines on certain maximum or minimum turning boundaries.

4. The operation path planning strategy does not consider barriers in an operation area or discontinuous barriers such as an inoperable area, cannot realize automatic path planning in a complex operation environment, and brings great challenges to unmanned driving.

Therefore, new unmanned solutions for agricultural vehicles are needed.

Disclosure of Invention

An object of the embodiments of the present invention is to provide an agricultural vehicle unmanned control method, system and agricultural vehicle, which are used for at least partially solving the technical problems.

In order to achieve the above object, an embodiment of the present invention provides an agricultural vehicle unmanned control method, including: acquiring closed farmland plot boundary data and discontinuous operation data acquired by a positioning system, wherein the discontinuous operation data comprises one or both of obstacle positioning data and non-operation area positioning data; acquiring vehicle steering angle data; and planning an unmanned automatic operation path according to the closed farmland plot boundary data, the discontinuous operation data and the vehicle steering angle data.

Preferably, the closed farmland parcel boundary data comprises a turning point position coordinate of a closed farmland parcel boundary; the obstacle positioning data comprises obstacle diagonal position coordinates; and the non-working area positioning data comprises non-working area outline position coordinates.

Preferably, the planning an unmanned autonomous working path according to the closed farmland parcel boundary data, the discontinuous working data and the vehicle steering angle data comprises: 1) determining sub-blocks and sub-block spans according to the position coordinates of the turning points; 2) performing one or both of: judging the sub-blocks to which the diagonal position coordinates of the obstacle belong, determining a left interval of the sub-block to which the smallest abscissa in the diagonal position coordinates of the obstacle belongs as a transverse minimum coordinate, and determining the transverse blocking span of the obstacle as the smallest even-numbered multiple span capable of meeting the actual span requirement of the diagonal position coordinates of the obstacle; judging the sub-blocks to which the preselected contour position coordinates of the non-operation area belong, determining the left interval of the sub-block corresponding to the point with the minimum sub-block ordinal number as a transverse minimum coordinate, and determining the transverse blocking span of the non-operation area as the minimum even-numbered multiple span which can meet the actual span requirements of the point with the minimum and maximum sub-block ordinal numbers; and 3) planning an unmanned automatic operation path according to the sub-blocks, the sub-block spans, the transverse minimum coordinates and the transverse blocking spans corresponding to the obstacles and/or the non-operation areas and the vehicle steering angle data.

Preferably, the planning the unmanned automated work path comprises: when no obstacle and/or no operation area exists in the sub-block operation line, controlling the agricultural vehicle to steer according to different head-to-tail steering angles of the ground according to the parity of the sub-block span, wherein the steering driving distance is the interval length corresponding to the parity of the different sub-block spans; and when an obstacle and/or a non-operation area exist in the sub-block operation row, the obstacle or the non-operation area boundary is equal to the sub-block field boundary, the steering angle is fixed to be 90 degrees, the minimum even-numbered interval span corresponding to the sub-block with the minimum ordinal number and the maximum ordinal number is used as the transverse blocking span, the agricultural vehicle is controlled to steer according to different field head and tail end steering angles according to the parity of the transverse blocking span, and the steering driving distance is the interval length corresponding to the parity of different transverse blocking spans.

Preferably, the agricultural vehicle unmanned control method further comprises: after the unmanned automatic operation path is planned, controlling the lifting and descending longitudinal position of the farm tool of each sub-block according to a preset safety distance before the farm vehicle reaches the ground, an obstacle or a non-operation area, wherein the controlling of the lifting and descending longitudinal position of the farm tool of each sub-block comprises one or both of the following steps: for the sub-block operation line without obstacles or in a non-operation area, the lifting longitudinal position of the farm tool is the difference between the vertical coordinate of the ground head boundary point and the safety distance, and the descending longitudinal position of the farm tool is the position of the farm vehicle when the turning is finished and the farm vehicle enters the next sub-block and the vehicle body is parallel to the sub-block operation line; and/or for the sub-block operation line with the obstacle or the non-operation area, the lifting longitudinal position of the farm tool is the difference between the longitudinal coordinate of the obstacle or the longitudinal coordinate of the non-operation area and the safety distance, and the descending longitudinal position of the farm tool is the position of the farm vehicle when the turning is completed and the farm vehicle enters the next sub-block and the vehicle body is parallel to the sub-block operation line.

Preferably, the agricultural vehicle unmanned control method further comprises any one or more of the following: comparing the vehicle steering angle data acquired by the steering sensor with the maximum value of the steering point angle of the planned unmanned automatic operation path, and judging that steering is finished when the vehicle steering angle data and the maximum value of the steering point angle of the planned unmanned automatic operation path are consistent; comparing the real-time vehicle position with a deviation value of the planned unmanned automatic operation path, and if the deviation value exceeds a preset deviation threshold value, performing deviation compensation on the agricultural vehicle; storing the closed farmland parcel boundary data, the obstacle positioning data, the non-working area positioning data and the vehicle steering angle data in real time; and displaying the closed farmland parcel boundary data, the obstacle positioning data, the non-work area positioning data, the vehicle steering angle data, and the planned unmanned automated work path.

The embodiment of the invention also provides a machine-readable storage medium, wherein the machine-readable storage medium is stored with instructions, and the instructions are used for enabling the machine to carry out the above-mentioned unmanned control method for the agricultural vehicle.

The embodiment of the invention also provides an agricultural vehicle unmanned control system, which comprises: the navigation function module comprises a positioning system and a non-continuous operation module, wherein the positioning system is used for acquiring boundary data of a closed farmland plot and non-continuous operation data, and the non-continuous operation data comprises one or both of obstacle positioning data and non-operation area positioning data; the steering angle acquisition module is used for acquiring vehicle steering angle data; and the path planning module is communicated with the navigation function module and the steering angle acquisition module and used for planning an unmanned automatic operation path according to the boundary data of the closed farmland plot, the discontinuous operation data and the vehicle steering angle data.

Preferably, the path planning module includes: the sub-block determining submodule is used for determining sub-blocks and sub-block spans according to the position coordinates of the steering point; a block processing sub-module for performing one or both of: judging the sub-blocks to which the diagonal position coordinates of the obstacle belong, determining a left interval of the sub-block to which the smallest abscissa in the diagonal position coordinates of the obstacle belongs as a transverse minimum coordinate, and determining the transverse blocking span of the obstacle as the smallest even-numbered multiple span capable of meeting the actual span requirement of the diagonal position coordinates of the obstacle; judging the sub-blocks to which the preselected contour position coordinates of the non-operation area belong, determining the left interval of the sub-block corresponding to the point with the minimum sub-block ordinal number as a transverse minimum coordinate, and determining the transverse blocking span of the non-operation area as the minimum even-numbered multiple span which can meet the actual span requirements of the point with the minimum and maximum sub-block ordinal numbers; and the path planning processing sub-module is communicated with the sub-block determining sub-module and the block processing sub-module and is used for planning an unmanned automatic operation path according to the sub-blocks, the sub-block spans, the transverse minimum coordinates and the transverse blocking spans corresponding to the obstacles and/or the non-operation area and the vehicle steering angle data.

Preferably, the path planning processing sub-module for planning the unmanned automatic work path includes: when no obstacle and/or no operation area exists in the sub-block operation line, controlling the agricultural vehicle to steer according to different head-to-tail steering angles of the ground according to the parity of the sub-block span, wherein the steering driving distance is the interval length corresponding to the parity of the different sub-block spans; and when an obstacle and/or a non-operation area exist in the sub-block operation row, the obstacle or the non-operation area boundary is equal to the sub-block field boundary, the steering angle is fixed to be 90 degrees, the minimum even-numbered interval span corresponding to the sub-block with the minimum ordinal number and the maximum ordinal number is used as the transverse blocking span, the agricultural vehicle is controlled to steer according to different field head and tail end steering angles according to the parity of the transverse blocking span, and the steering driving distance is the interval length corresponding to the parity of different transverse blocking spans.

Preferably, the agricultural vehicle unmanned control system further comprises: the whole vehicle control module is used for controlling the lifting and descending longitudinal positions of the agricultural tools of each sub-block according to the preset safe distance before the agricultural vehicle reaches the ground, the obstacle or the non-operation area after the unmanned automatic operation path is planned; wherein, whole car control module is used for controlling the agricultural implement of each sub-piecemeal to promote and descend vertical position and include: for the sub-block operation line without obstacles or in a non-operation area, the lifting longitudinal position of the farm tool is the difference between the vertical coordinate of the ground head boundary point and the safety distance, and the descending longitudinal position of the farm tool is the position of the farm vehicle when the turning is finished and the farm vehicle enters the next sub-block and the vehicle body is parallel to the sub-block operation line; and/or for the sub-block operation line with the obstacle or the non-operation area, the lifting longitudinal position of the farm tool is the difference between the longitudinal coordinate of the obstacle or the longitudinal coordinate of the non-operation area and the safety distance, and the descending longitudinal position of the farm tool is the position of the farm vehicle when the turning is completed and the farm vehicle enters the next sub-block and the vehicle body is parallel to the sub-block operation line.

Preferably, the agricultural vehicle unmanned control system further comprises any one or more of: the angle feedback module is used for comparing the vehicle steering angle data acquired by the steering sensor with the maximum value of the steering point angle of the planned unmanned automatic operation path, and judging that the steering is finished when the vehicle steering angle data and the maximum value of the steering point angle of the planned unmanned automatic operation path are consistent; the track deviation rectifying module is used for comparing the real-time vehicle position with a deviation value of the planned unmanned automatic operation path, and if the deviation value exceeds a preset deviation threshold value, performing deviation compensation on the agricultural vehicle; the data storage module is used for storing closed farmland plot boundary data, the obstacle positioning data, the non-operation area positioning data and the vehicle steering angle data in real time; and the state display module is used for displaying the closed farmland parcel boundary data, the obstacle positioning data, the non-operation area positioning data, the vehicle steering angle data and the planned unmanned automatic operation path.

The embodiment of the invention also provides an agricultural vehicle which comprises the unmanned control system of the agricultural vehicle.

Through the technical scheme, the embodiment of the invention has the following technical effects: the embodiment of the invention completes automatic path planning design by combining the positioning technology and the steering angle acquisition technology, not only exerts the high precision and high reliability of positioning systems such as a GPS (global positioning system), but also flexibly introduces the technical advantages of acquiring the steering angle by a vehicle, provides an obstacle avoidance strategy for obstacles and non-operation areas, effectively solves the difficulty of automatic path planning in the unmanned driving process, and is a beneficial scheme with high efficiency, stability and cost saving.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic flow chart of an agricultural vehicle driverless control method of an embodiment of the invention;

FIG. 2 is a schematic flow chart diagram illustrating a method for obtaining coordinates of a turning point location in a preferred embodiment;

FIG. 3 is a flow chart illustrating a method for planning an unmanned automated work path in accordance with a preferred embodiment of the present invention;

FIG. 4 is a schematic structural diagram of an agricultural vehicle unmanned control system according to another embodiment of the invention;

FIG. 5 is a schematic diagram of the structure of a path planning module in the preferred embodiment of the present invention;

FIG. 6 is a schematic illustration of closed field plot boundary polygonization in an example of an embodiment of the present invention;

FIG. 7 is a schematic illustration of exemplary obstacle or non-work area coordinate calibration in accordance with an embodiment of the present invention;

FIG. 8 is a schematic diagram of an exemplary closed field equidistant total patch strategy according to an embodiment of the present invention;

FIG. 9 is a schematic diagram of a sub-block and obstacle steering strategy in an example of an embodiment of the present invention; and

FIG. 10 is a schematic view of exemplary implement elevation and lowering longitudinal position coordinates in accordance with an embodiment of the present invention.

Description of the reference numerals

1. A navigation function module; 2. a steering angle acquisition module; 3. a path planning module; 4. a vehicle control module; 5. an output execution module; 6. an angle feedback module; 7. a trajectory rectification module; 8. a data storage module; 9. a status display module;

301. a sub-block determination sub-block; 302. the barrier blocking processing submodule; 303. a non-operation area blocking processing submodule; 304. and a path planning processing submodule.

Detailed Description

The following detailed description of embodiments of the invention refers to the accompanying drawings. It should be understood that the detailed description and specific examples, while indicating the present invention, are given by way of illustration and explanation only, not limitation.

Fig. 1 is a schematic flow chart of an unmanned control method for an agricultural vehicle according to an embodiment of the present invention, wherein the agricultural vehicle includes, but is not limited to, a tractor, and for convenience of description, the tractor is taken as an example below. In addition, the unmanned field is similar to the field of 'automatic farming' of agricultural machinery such as tractors and the like, and is a specific automatic operation mode, and in the automatic operation mode, the coordinate calibration of the boundary turning point of the closed farmland plot, the formulation of the equidistant total block and sub-block strategy of the closed farmland plot, the planning of the straight-going and turning paths of the closed farmland, the lifting control strategy of farm implements and the like need to be completed. Wherein, for a designated closed farmland plot operation area, the periphery boundary has closeness and diversity, and usually, the boundary of the operation area is composed of irregular multi-segment curves.

As shown in fig. 1, the agricultural vehicle unmanned control method of the embodiment of the invention may include the steps of:

and S100, acquiring closed farmland plot boundary data and discontinuous operation data acquired by a positioning system.

Wherein the non-continuous operation data comprises one or both of obstacle positioning data and non-operation area positioning data.

Step S200, vehicle steering angle data is acquired.

And step S300, planning an unmanned automatic operation path according to the boundary data of the closed farmland plot, the discontinuous operation data and the vehicle steering angle data.

In step S100, the positioning system is installed on the agricultural vehicle, and a satellite navigation system, preferably a GPS, is adopted, and the GPS is mainly taken as an example hereinafter.

Further, for step S100, the closed field plot boundary data may include turning point position coordinates of the closed field plot boundary. FIG. 2 is a flow chart illustrating a method for obtaining coordinates of a turning point position in a preferred embodiment. As shown in fig. 2, the following steps may be included:

and step S110, collecting the position coordinates of the boundary curve outline of the closed farmland plot.

Usually, the boundary of the farmland plot to be worked is an irregular multi-section curve. The tractor is controlled by the tractor for the first time to clockwise detour the curve boundary of the land to be operated for a circle, and the GPS is turned on in the detour process. In the bypassing process of the tractor, the left wheel of the tractor is tightly attached to the boundary of the land to be operated, and the bypassing speed is kept low and constant. Meanwhile, every time the vehicle travels a proper distance, the GPS positioning system collects the current vehicle position coordinate Z_n(x_Zn，y_Zn) And sending the data to the vehicle positioning data flash memory card for storage. The judgment and selection principle of the proper driving distance is as follows: the greater the curvature of the plot boundary curve, the smaller the distance should be, i.e., to increase the real-time vehicle position seatingThe target sampling frequency and vice versa.

And step S120, performing linear polygonization on the zone boundary and selecting the position coordinates of the turning point.

In order to realize the unmanned driving of the tractor, discrete points of a curve of a closed farmland plot boundary to be operated need to be subjected to polygonization, and a plurality of sections of curves are subjected to folding line transformation to form a closed polygon under the principle of being close to an original boundary as much as possible. Specifically, a rectangular coordinate system is established, discrete points of a boundary curve stored in the flash memory card for positioning data of the vehicle are drawn in the rectangular coordinate system, each discrete point is fitted to form a closed multi-segment line segment, at least one group of parallel straight lines is ensured, one line segment is taken, any end point of the line segment is taken as an initial position point, and A is defined as₀(x_A0，y_A0). The vertex of the closed polygon is a turning point, and the position coordinate of the mth turning point in the clockwise direction is defined as A_m(x_Am，y_Am)。

Further, for step S100, the obstacle location data may include obstacle diagonal position coordinates, and the non-working area location data may include non-working area contour position coordinates. In the embodiment of the invention, small-area shelters such as sand stones, trees and the like randomly distributed in the range of the farmland plots to be operated are defined as obstacles, large-area barriers such as ridges, ditches, grasslands and the like are defined as non-operation areas, and the obstacles and the non-operation areas need to be avoided or bypassed in the operation process of the tractor. In order to realize the unmanned driving of the tractor, the positioning data of the obstacles and the non-working area, in particular the coordinates of the diagonal positions of the obstacles and the coordinates of the outline positions of the non-working area, also need to be acquired. For the obstacle, the tractor driver only needs to operate the tractor to acquire 2 diagonal position coordinates of the obstacle, which are recorded as B_i(x_Bi，y_Bi) (ii) a For the non-operation area, the tractor is controlled by the tractor to move around the non-operation area for a circle, and appropriate amount of contour coordinate information is recorded uniformly and equidistantly and is marked as C_j(x_Cj，y_Cj). The vehicle positioning data flash memory card will record the diagonal position coordinates B of all the obstacles in the range of the closed farmland plot_i(x_Bi，y_Bi) And contour coordinates C of all non-working areas_j(x_Cj，y_Cj)。

In step S200, the vehicle steering angle data may be obtained by performing coordinate calculation on the data collected by the GPS, or the vehicle steering angle data may be collected by configuring a steering sensor on the vehicle, and the steering sensor collection manner will be mainly exemplified below.

Further, for step S200, the vehicle steering angle data collected by the steering sensor is in an accumulated form, and the steering sensor is combined with the GPS, which is beneficial to dealing with the great challenges brought by the variability of the vehicle body angle and the complexity of the work path planning in the steering process of the tractor.

In step S300, the obstacle location data and the non-working area location data may exist only or both, and those skilled in the art may select them according to the actual situation of the closed farmland parcel, which is not limited by the embodiment of the present invention.

Further to step S300, fig. 3 is a flowchart illustrating a method for planning an unmanned automatic work path according to a preferred embodiment of the present invention. As shown in fig. 3, step S300 may be implemented by:

and S310, determining the sub-blocks and the sub-block spans according to the position coordinates of the turning points.

Further, the step S310 may include steps S311 to S313 (not shown in fig. 3).

Step S311, calculates the maximum angle value of each turning point of the boundary according to the coordinates of the turning point position.

The included angle (usually an acute angle) formed by two adjacent straight lines at the turning point is the maximum value of the angle corresponding to the turning point, and the maximum value is the maximum turning angle allowed when the tractor is unmanned and turns at the boundary of the straight line land parcel.

Specifically, the position coordinates A of each turning point are read from the flash memory card for positioning the vehicle data_m(x_Am，y_Am) And calculating the included angle between adjacent straight lines of the closed land to be operated, thereby determining the maximum value of the angle of the turning point. In addition, can alsoAnd calculating the length of any line segment of the boundary of the polygonal plot according to the position coordinates of each turning point.

Step S312, calculating the transverse span x of the land parcel_maxAnd calculating the total number of the equal-width blocks according to the width of the farm tool.

Specifically, each turning point A is read from the vehicle-positioning data flash memory card_mAbscissa x of_AmAccording to the principle that at least one group of parallel line segments is fitted when the discrete points are fitted, the distance between a selected pair of parallel line segments is the transverse span x of the land parcel_max. Defining the width d of the farm tool, and ensuring that the problems of heavy plowing, missing plowing, multiple traveling distances and the like are avoided in the unmanned driving process, wherein the total block number of the closed farmland with equal width is N ═ x_max/d-1。

Step 313, calculating the block of the direct line operation in a regionalization mode, and classifying the region to which each turning point belongs.

Specifically, at a first turning point A₁Abscissa x_A1For the initial value of the transverse coordinate, the width d of the farm tool is used for the amplification to establish an operation sub-block transverse partition set X_j[x_A1+jd，x_A1+(j+1)d]. Sequentially judging the abscissa x of each steering point_iAnd the sub-block ordinal number j corresponding to each turning point can be known from the section. And (4) arranging the ordinal numbers of the sub-blocks from small to large, and calculating the interval difference value of the ordinal number j of the adjacent sub-blocks, namely the sub-block span. If the sub-block span is 0, corresponding to two turning points, the turning points are regarded as head and tail equivalent points, so that the sub-block ordinal number p and the sub-block span number q can be determined, and each sub-block is marked as B_pqDividing the total block number N and the sub-blocks B_pqAnd the parameters are subsequently used for path planning. It should be emphasized that the sub-blocks are determined based on the total number of the sub-blocks, the belonging intervals of the abscissa of all the turning points are analyzed according to the breadth of the farm implement, and then the divided operation sub-blocks are divided, the head end and the tail end in the same sub-block respectively keep the same turning angle, the ordinal number of each sub-block is divided according to the belonging interval of the turning point, and the sum of the span of each sub-block is equal to the total number of the sub-blocks.

And step S320, determining the transverse minimum coordinate and the transverse obstruction span of the obstacle according to the diagonal position coordinate of the obstacle.

Specifically, the diagonal position coordinate B of the obstacle is judged₁And B₂The sub-blocks to which the sub-blocks belong are determined₁And B₂The left interval of the sub-block to which the middle abscissa is minimum is taken as the transverse minimum coordinate, and the transverse obstruction span of the obstacle is determined to meet B₁And B₂The minimum even multiple span required. More specifically, the diagonal position coordinates B of the 2 collected obstacles are read₁(x_B1，y_B1)、B₂(x_B2，y_B2) Judgment of B₁、B₂The associated job is divided into horizontal sections, and x is assumed_B1<x_B2Then get B₁Taking the left interval of the belonged partition as a transverse minimum coordinate, and taking B₁、B₂And taking the minimum even multiple interval span as the transverse blocking span of the barrier.

And step S330, determining the transverse minimum coordinate and the transverse blocking span of the non-working area according to the contour position coordinate of the non-working area.

Specifically, the sub-blocks to which the preselected contour position coordinates of the non-working area belong are judged, the left section of the sub-block corresponding to the point with the minimum sub-block ordinal number is determined as the transverse minimum coordinate, and the transverse blocking span of the non-working area is determined to be the minimum even-numbered multiple span which can meet the actual span requirements of the point with the minimum and maximum sub-block ordinal numbers. More specifically, for non-working areas, the collected contour coordinate information C of the uniform equidistant recording is read_j(x_Cj，y_Cj) Similar to the processing of the obstacle, C is sequentially determined_jAnd the left interval of the partition corresponding to the smallest sub-partition ordinal number is taken as a transverse minimum coordinate, and the interval span corresponding to the smallest even multiple of the partition corresponding to the smallest sub-partition ordinal number and the largest sub-partition ordinal number is taken as the transverse blocking span of the non-operation area. Therefore, in the embodiment of the invention, even number edge zoning processing is carried out on the obstacles and the non-working areas, namely in the process of carrying out area division on the obstacles and the non-working areas existing in the closed farmland plots, the zone to which the obstacles and the non-working areas belong is judged according to the abscissa of the diagonal position coordinate or the outline position coordinate, and the left side is judgedThe interval is a value smaller than and adjacent to the minimum abscissa, and the right interval is a value larger than the maximum abscissa and ensuring that the number of the spanned subblocks is even.

It is understood that, depending on the actual situation of the closed farmland plot, only one or both of the steps S320 and S330 may be performed.

Step S340, planning an unmanned automatic operation path according to the sub-blocks, the sub-block spans, the transverse minimal coordinates and the transverse blocking spans corresponding to the obstacles and/or the non-operation areas, and the vehicle steering angle data.

Specifically, when no obstacle and/or no-operation area exists in the sub-block operation line, the agricultural vehicle is controlled to steer according to different steering angles at the head end and the tail end of the ground according to the parity of the sub-block span q, wherein the steering driving distance is the interval length corresponding to the parity of different sub-block spans; and when an obstacle and/or a non-operation area exist in the sub-block operation row, the obstacle or the non-operation area boundary is equal to the sub-block field boundary, the steering angle is fixed to be 90 degrees, the minimum even-numbered interval span corresponding to the sub-block with the minimum ordinal number and the maximum ordinal number is used as the transverse blocking span, the agricultural vehicle is controlled to steer according to different field head and tail end steering angles according to the parity of the transverse blocking span, and the steering driving distance is the interval length corresponding to the parity of different transverse blocking spans.

According to the parity of the sub-block span q, controlling the agricultural vehicle to steer according to different steering angles at the head end and the tail end of the ground specifically comprises the following steps: when the span q of the sub-blocks is odd, when the sub-block is turned around at the margin of the land head, the agricultural vehicle runs the land blocks with the interval length of (q +1)/2 according to the section of steering angle, and when the sub-block is turned around at the margin of the land head, the agricultural vehicle runs the land blocks with the interval length of (q-1)/2 according to the section of steering angle; when the sub-block span q is an even number, when the sub-block is turned around at the margin of the land head of the sub-block, the agricultural vehicle runs the land with the interval length of q/2 according to the section of turning angle, and when the sub-block is turned around at the margin of the land head of the sub-block, the agricultural vehicle runs the land with the interval length of q/2-1 according to the section of turning angle; when entering the next sub-block, the turning directions of the head end and the tail end are opposite to that of the previous sub-block, and in the same sub-block, the turning directions of the head end and the tail end are the same. It can be understood that when there is an obstacle and/or a non-working area in the sub-block working line, a steering strategy consistent with the sub-block steering strategy is adopted, and therefore, detailed description is omitted.

Particularly, when all the operation sub-blocks on one side of the obstacle or the non-operation area complete automatic operation, the tractor needs to go around to close the boundary of the farmland plot and be in a non-operation state so as to prevent the tractor from damaging the plot or repeating the operation when the tractor runs to the start of the operation sub-blocks on the other side of the obstacle or the non-operation area. Wherein, the tractor is in the automatic operation in-process, sends the incorgruous instruction of turning to by vehicle control unit when getting into next sub-piecemeal.

With continued reference to fig. 1, in a more preferred embodiment, the agricultural vehicle unmanned control method further comprises:

and S400, after the unmanned automatic operation path is planned, controlling the lifting and descending longitudinal positions of the farm tools of each sub-block according to the preset safety distance before the farm vehicle reaches the ground, the obstacle or the non-operation area.

The safety distance is a distance which needs to be reserved before the tractor reaches the ground or an obstacle and a non-operation area boundary in the unmanned driving process of the tractor due to the safety driving consideration, so that the tractor is ensured to decelerate and switch the state of the farm tool, and the problems that the ground is damaged, the obstacle cannot be avoided, the vehicle body turns on one side and the like in the steering process are avoided.

Specifically, the lifting and descending longitudinal positions of the sub-block agricultural implements are determined according to the inherent deceleration safety distance of the tractor. The agricultural implement suspension mechanism and the steering hydraulic valve bank are respectively used for the automatic steering control of the vehicle during the agricultural implement state switching and the steering mode under the operation mode/the steering mode. In the switching process of the two processes of sub-block straight-going operation and sub-block turning and rail re-entering, the tractor usually needs to complete the lifting or descending operation of farm tools to ensure safe operation. The vehicle control unit sends an agricultural implement lifting control signal when the vehicle control unit is at a certain safe distance from the ground, an obstacle or a non-working area, and sends an agricultural implement descending control signal when the vehicle control unit is at a steering completion position. For the sub-block operation line without obstacles or in a non-operation area, the lifting longitudinal position of the farm tool is the difference between the vertical coordinate of the ground head boundary point and the safety distance, and the descending longitudinal position of the farm tool is the position of the farm vehicle when the farm vehicle finishes steering and enters the next sub-block and the vehicle body is parallel to the sub-block operation line; and/or for the sub-block operation line with the obstacle or the non-operation area, the lifting longitudinal position of the farm tool is the difference between the longitudinal coordinate of the obstacle or the non-operation area and the safety distance, and the descending longitudinal position of the farm tool is also the position of the tractor when the tractor finishes turning to the next sub-block under the rail and the vehicle body is parallel to the sub-block operation line.

The unmanned control method for the agricultural vehicle of the embodiment of the invention also comprises some error processing schemes. For example, the steering angle data of the vehicle collected by the steering sensor is accumulated, so that accumulated errors may occur, which may cause lateral or deviation between the actual position of the vehicle and the automatic path planning during the steering process, and the existence of obstacles or non-working areas may cause the same kind of errors. In this regard, the agricultural vehicle unmanned control method according to the embodiment of the present invention may further include: and comparing the vehicle steering angle data acquired by the steering sensor with the maximum value of the steering point angle of the planned unmanned automatic operation path, and judging that the steering is finished when the vehicle steering angle data acquired by the steering sensor and the maximum value of the steering point angle of the planned unmanned automatic operation path are consistent. That is, the collected vehicle steering angle data is fed back in real time and compared with the data in the calculated planned path to judge whether steering is completed. Further, the agricultural vehicle unmanned control method according to the embodiment of the present invention may further include: and comparing the real-time vehicle position with the deviation value of the planned unmanned automatic operation path, and if the deviation value exceeds a preset deviation threshold value, performing deviation compensation on the agricultural vehicle. Namely, the track of the vehicle is corrected through a deviation threshold value until the automatic operation of the closed farmland plot is completely finished.

In a more preferred embodiment, the agricultural vehicle unmanned control method further includes: and storing the closed farmland parcel boundary data, the obstacle positioning data, the non-operation area positioning data and the vehicle steering angle data in real time. For example, by the above-mentioned vehicle-positioning data flash memory card, so as to be called in the above-mentioned steps.

In a more preferred embodiment, the agricultural vehicle unmanned control method further includes: displaying the closed field plot boundary data, the obstacle positioning data, the non-work area positioning data, the vehicle steering angle data, and the planned unmanned automated work path. For example, the display may be made through an industrial display screen of the agricultural vehicle.

In summary, compared with the prior art, the agricultural vehicle unmanned control method provided by the embodiment of the invention at least has the following advantages:

1) different from the single GPS positioning navigation technology in the prior art, the embodiment of the invention adopts the mode of combining the positioning navigation technology with the technology (such as the tractor self-sensing technology) for determining the vehicle steering angle by the tractor self to complete the automatic path planning design, thereby not being limited to the complexity of realizing the steering of the GPS navigation system during the automatic operation, not only playing the high precision and high reliability of the GPS navigation system, but also flexibly introducing the advantages of the vehicle self-sensing technology, also providing an obstacle avoidance strategy about obstacles and non-operation areas, effectively solving the automatic path planning difficulty in the unmanned driving process, and being a beneficial scheme with high efficiency, stability and cost saving.

2) The embodiment of the invention introduces a real-time deviation correction feedback strategy, and effectively reduces the accumulated error caused by the vehicle steering sensor.

3) The embodiment of the invention adopts a sub-block transverse span self-adaptive steering strategy to realize the optimal steering distance and intelligent steering angle, and is different from various steering mode technologies of semi-circle, pear shape, fishtail shape and the like in the prior art. Specifically, the steering angle in the embodiment of the invention is not fixed, in the automatic operation process, the steering angle is suitable for the straight line or the steering angle of the steering point where the polygon of the boundary of the closed farmland plot is located when the tractor steers for the first time, and the steering angle is the supplementary angle of the steering point when the tractor steers for the second time, so that the three steering modes are different from the three steering modes in the prior art. In addition, the sub-block turning interval length depends on the number of each sub-block, and the turning interval lengths at the head end and the tail end in the odd-even mode are different. In the process of automatic operation, the steering interval length obtained intelligently can save more land areas, the risks of wrong cultivation, repeated cultivation and missing cultivation do not exist, the operation quality and efficiency are greatly improved, and a new possible mode is provided for cluster operation in the future.

4) The embodiment of the invention provides a control strategy for interval processing of position coordinates of an obstacle and an even number edge of a non-working area, which is different from a machine vision obstacle avoidance strategy in the prior art, and is mainly characterized in that additional sensing equipment or a control system is not required to be loaded, only a self GPS positioning system is required to collect diagonal position coordinates of each obstacle or outline position coordinates of the non-working area, the left interval of the partition corresponding to the minimum sub-partition ordinal number is taken as a transverse minimum coordinate by judging the transverse partition of the working sub-partition to which a position coordinate set belongs, and the minimum even number multiple interval span corresponding to the minimum sub-partition ordinal number and the maximum sub-partition ordinal number is taken as the transverse blocking span of the non-working area. Compared with the existing machine vision system with high economic cost, the obstacle avoidance control strategy of the embodiment of the invention is not influenced by the surrounding operation environment such as light intensity, weather, surface color of farmland plots and the like, and does not need additional development cost of the machine vision system, so that the method is a convenient, efficient, economic and reliable control scheme.

Fig. 4 is a schematic structural diagram of an agricultural vehicle unmanned control system according to another embodiment of the present invention, which is based on the same inventive concept as the agricultural vehicle unmanned control method according to the above-described embodiment.

As shown in fig. 4, an agricultural vehicle unmanned control system of an embodiment of the present invention includes: the navigation function module 1 comprises a positioning system, and is used for acquiring boundary data of a closed farmland plot and discontinuous operation data, wherein the discontinuous operation data comprises one or both of obstacle positioning data and non-operation area positioning data; the steering angle acquisition module 2 is used for acquiring vehicle steering angle data; and the path planning module 3 is communicated with the navigation function module 1 and the steering angle acquisition module 2 and is used for planning an unmanned automatic operation path according to the boundary data of the closed farmland plots, the discontinuous operation data and the vehicle steering angle data.

Wherein the closed farmland plot boundary data comprises a turning point position coordinate of a closed farmland plot boundary; the obstacle positioning data comprises obstacle diagonal position coordinates; and the non-working area positioning data comprises non-working area outline position coordinates.

In a preferred embodiment, the positioning system is a GPS system, and the navigation function module 1 may further include a trajectory recorder for recording the planned unmanned automatic work path; the steering angle acquisition module 2 may include a steering angle sensor provided on the vehicle, and may also include other sensors such as a vehicle speed sensor, as needed.

Fig. 5 is a schematic structural diagram of the path planning module 3 in the preferred embodiment of the present invention. As shown in fig. 5, the path planning module 3 may include:

the sub-block determining submodule 301 is used for determining sub-blocks and sub-block spans according to the position coordinates of the turning point;

a block processing sub-module 302 for performing one or both of: judging the diagonal position coordinates of the obstacle (B above)₁And B₂) Determining the left interval of the sub-block to which the smallest abscissa in the diagonal position coordinates of the obstacle belongs as the transverse minimum coordinate, and determining the transverse blocking span of the obstacle as the smallest even-numbered multiple span which can meet the actual span requirement of the diagonal position coordinates of the obstacle; judging the sub-blocks to which the preselected contour position coordinates of the non-operation area belong, determining the left interval of the sub-block corresponding to the point with the minimum sub-block ordinal number as a transverse minimum coordinate, and determining the transverse blocking span of the non-operation area as the minimum even-numbered multiple span which can meet the actual span requirements of the point with the minimum and maximum sub-block ordinal numbers;

and the path planning processing submodule 303 is in communication with the sub-block determining submodule 301 and the block processing submodule 302, and is configured to plan an unmanned automatic operation path according to the sub-blocks, the sub-block spans, the transverse minimum coordinates and the transverse blocking spans corresponding to the obstacles and/or the non-operation area, and the vehicle steering angle data.

Preferably, the path planning processing sub-module 303 for planning the unmanned automatic work path includes: when no obstacle and/or no operation area exists in the sub-block operation line, controlling the agricultural vehicle to steer according to different head-to-tail steering angles of the ground according to the parity of the sub-block span, wherein the steering driving distance is the interval length corresponding to the parity of the different sub-block spans; and when an obstacle and/or a non-operation area exist in the sub-block operation row, the obstacle or the non-operation area boundary is equal to the sub-block field boundary, the steering angle is fixed to be 90 degrees, the minimum even-numbered interval span corresponding to the sub-block with the minimum ordinal number and the maximum ordinal number is used as the transverse blocking span, the agricultural vehicle is controlled to steer according to different field head and tail end steering angles according to the parity of the transverse blocking span, and the steering driving distance is the interval length corresponding to the parity of different transverse blocking spans.

It will be appreciated that the path planning module 3 may be configured using an automatic path planning processor, depending on the functionality of the various sub-modules of the path planning module 3.

Referring again to fig. 4, in a preferred embodiment, the agricultural vehicle unmanned control system may further include: and the whole vehicle control module 4 is used for controlling the lifting and descending longitudinal positions of the farm tools of each sub-block according to the preset safe distance before the farm vehicle reaches the ground, the obstacle or the non-operation area after planning the unmanned automatic operation path. For the sub-block operation line without obstacles or in the non-operation area, the lifting longitudinal position of the farm tool is the difference between the vertical coordinate of the ground head boundary point and the safety distance, and the descending longitudinal position of the farm tool is the position of the farm vehicle when the turning is finished and the farm vehicle enters the next sub-block and the vehicle body is parallel to the sub-block operation line; and/or for the sub-block operation line with the obstacle or the non-operation area, the lifting longitudinal position of the farm tool is the difference between the longitudinal coordinate of the obstacle or the longitudinal coordinate of the non-operation area and the safety distance, and the descending longitudinal position of the farm tool is the position of the farm vehicle when the turning is completed and the farm vehicle enters the next sub-block and the vehicle body is parallel to the sub-block operation line.

It will be appreciated that the vehicle control module 4 may be configured with a vehicle control unit of the vehicle. Corresponding to the whole vehicle control module 4, the agricultural vehicle unmanned control system may further include an output execution module 5, where the output execution module 5 includes, for example, an agricultural implement suspension mechanism and a steering hydraulic valve set of the vehicle, and is configured to receive a control instruction of the whole vehicle control module to enable the vehicle to execute a corresponding action.

Referring again to fig. 4, in a preferred embodiment, the agricultural vehicle unmanned control system may further include: the angle feedback module 6 is used for comparing the vehicle steering angle data acquired by the steering sensor with the maximum value of the steering point angle of the planned unmanned automatic operation path, and judging that the steering is finished when the vehicle steering angle data and the maximum value of the steering point angle of the planned unmanned automatic operation path are consistent; and/or the track deviation rectifying module 7 is used for comparing the real-time vehicle position with the deviation value of the planned unmanned automatic operation path, and if the deviation value exceeds a preset deviation threshold value, performing deviation compensation on the agricultural vehicle. Here, the angle feedback module 6 and the trajectory rectification module 7 form a real-time rectification feedback strategy, which can effectively reduce the accumulated error caused by the vehicle steering sensor.

In a more preferred embodiment, the agricultural vehicle unmanned control system may further include: the data storage module 8 is used for storing the boundary data of the closed farmland plot, the positioning data of the obstacles, the positioning data of the non-working area and the steering angle data of the vehicle in real time; and/or a state display module 9 for displaying the closed farmland parcel boundary data, the obstacle positioning data, the non-working area positioning data, the vehicle steering angle data, and the planned unmanned automatic working path. The data storage module 8 includes the vehicle positioning data flash memory card, and the status display module 9 includes the driving display screen.

It should be noted that the connection relationships between the modules in fig. 4 and 5 are schematic, and the embodiment of the present invention is not limited to the connection relationships shown in the drawings.

For details and effects of other embodiments of the unmanned control system for agricultural vehicles according to another embodiment of the present invention, reference may be made to the above embodiments related to the unmanned control method for agricultural vehicles, and further description is omitted here.

The application of the unmanned control method and system for agricultural vehicles according to the embodiments of the present invention is specifically described below by way of example, and in the example, both an obstacle and a non-working area are provided, but it is understood that the example method is also applicable to a case where only one of the obstacle and the non-working area is provided. This example is directed to a closed field plot and specifically includes the following several partial steps.

Step 1: the method comprises the steps of closed farmland plot boundary polygonization, acquisition of steering point and barrier positioning data, linear polygonization of area boundary and selection of coordinates of steering point positions.

Fig. 6 is a schematic illustration of closed field plot boundary polygonization in an example of an embodiment of the present invention. Referring to fig. 6, the tractor is controlled by the tractor for the first time to make a clockwise detour around the curve boundary of the land to be worked for one circle, and the GPS positioning system is turned on in the detour process. The left wheel of the tractor is tightly attached to the curve boundary of the land to be operated, and the GPS positioning system collects the current vehicle position coordinate Z every time the tractor runs for a proper distance_n(x_Zn，y_Zn) And sends it to the vehicle positioning data flash card. As shown in FIG. 6, the initial position coordinate recording point of the vehicle is Z₁After running clockwise at a low speed for a suitable distance, at Z₂The point records the 2 nd position coordinate, and so on. Establishing a rectangular coordinate system, and storing the discrete points Z of the boundary curve stored in the flash memory card for the vehicle positioning data_n(x_Zn，y_Zn) And drawing in a rectangular coordinate system, and fitting each discrete point to form a closed multi-segment line segment. As shown in fig. 6, the discrete point Z₁～Z₂₃The method can fit 9 line segments connected end to end, and the line segments are basically matched with the boundary of the plot curve, so that the fitting degree is high. In particular, the discrete point Z₁～Z₄Fitting and shifting to the right for a certain distance (half of the width of the farm implement) to obtain a line segment A₀A₁In the same way, all the line segments A can be obtained_mA_m+1(m-0, … …, 8). In these line segments, analysis reveals A₀A₁And A₅A₆Approximately parallel, thereby A₀(x_A0，y_A0) As initial position point, A_m(x_Am，y_Am) And the position coordinates of the turning point of each line segment.

The single point collects the diagonal position coordinates of 2 small-area obstacles, and collects the contour coordinate information of a proper amount of large-area non-operation area uniformly and equidistantly. FIG. 7 is a schematic illustration of exemplary obstacle or non-work area coordinate calibration in accordance with an embodiment of the present invention. Referring to fig. 7, for a small-area obstacle, the tractor driver only needs to operate the tractor to acquire 2 diagonal position coordinates of the obstacle, which are marked as B_i(x_Bi，y_Bi) (ii) a For a large-area non-operation area (partition), a tractor is required to be operated by a tractor to move around the non-operation area for a circle, and appropriate amount of contour coordinate information is recorded uniformly and equidistantly and is marked as C_j(x_Cj，y_Cj). The vehicle positioning data flash memory card will record the diagonal position coordinates B of all the obstacles in the range of the closed farmland plot_i(x_Bi，y_Bi) And contour coordinates C of all non-working areas_j(x_Cj，y_Cj)。

Step 2: and (3) performing interval processing on equidistant blocks and turning points of a closed farmland, and performing interval processing on even-numbered edges of coordinates of obstacles or non-working areas.

And calculating the maximum angle value of each turning point of the boundary according to the position coordinates of the turning point. Reading position coordinates A of each steering point from a vehicle positioning data flash memory card_m(x_Am，y_Am) Calculating the steering angle of the closed land block to be operated:

in particular, the absolute value of the angle is the dragThe maximum steering angle of the tractor at the corresponding steering point is the angle maximum of the steering point. The symbol of the straight line corresponds to the straight line A of the tractor on the boundary of the land_mA_m+1With the sign positive, the tractor turns to the right at the plot boundary, and vice versa. Meanwhile, the length of any line segment of the boundary of the polygonal plot can be calculated according to the position coordinates of each turning point:

calculating the transverse span x of the land mass_maxAnd calculating the total block number N of the equal width according to the width of the farm tool. Referring to FIG. 7, a set of approximately parallel line segments A is selected₀A₁And A₅A₆The distance between the parallel line segments is the transverse span x of the land parcel_max. Defining the width d of the farm tool, and calculating the total block number of the closed farmland with equal width in order to avoid the problems of heavy plowing, missing plowing, multiple traveling distances and the like in the unmanned driving process: n ═ x_A6-x_A1)/d]-1＝20。

FIG. 8 is a schematic diagram of an exemplary closed field equidistant total patch strategy in accordance with an embodiment of the present invention. Referring to FIG. 8, at a first turning point A₁Abscissa x_A1For the initial value of the transverse coordinate, the width d of the farm tool is used for the amplification to establish an operation sub-block transverse partition set X_j[x_A1+jd，x_A1+(j+1)d](j ═ 0, 1.., 20). Sequentially judging the abscissa x of each steering point_AiIn the section to which the steering wheel belongs, the sub-block ordinal number j corresponding to each steering wheel is known as follows: { A₁→0；A₂→6；A₃→12；A₄→15；A₅→20；A₆→20；A₇→15；A₈→ 8 }. Arranging the ordinal numbers of the sub-blocks from small to large: { A₁→0；A₂→6；A₈→8；A₃→12；A₄→15；A₇→15；A₅→20；A₆→ 20}, compute the adjacent sub-partition ordinal j interval difference: { A₂-A₁＝6；A₈-A₂＝2；A₃-A₈＝4；A₄-A₃＝3；A₇-A₄＝0；A₅-A₇＝5；A₆-A₅0 }. Obviously, there is A₄、A₇And A₅、A₆The difference value of the ordinal number interval of the blocks is 0, then the turning point A is₄And A₇、A₅And A₆Considered as head-to-tail equivalence. From this, the sub-blocks B can be determined_pqThe method specifically comprises the following steps: { A₁→A₂：B₁₆；A₂→A₈：B₂₂；A₈→A₃：B₃₄；A₃→A₄：B₄₃；A₅→A₇：B₅₅}。

Referring again to fig. 8, for a small-area obstacle, the acquired diagonal position coordinates B of 2 of the obstacle are read₁(x_B1，y_B1)、B₂(x_B2，y_B2) Easy judgment of B₁、B₂All belong to the operation sub-block transverse partition 15. Get B₁Left interval (x) of the partition_A1+14d) as the transverse minimum coordinate, take B₁、B₂Corresponding to 2 times interval span as the transverse blocking span of the obstacle, so that the transverse interval of the obstacle is (x)_A1+14d，x_A1+16 d). And for large-area partitions, reading the collected contour coordinate information C recorded at uniform equal intervals_j(x_Cj，y_Cj) Sequentially determining C_jThe sub-block of the job is laterally partitioned into { C₁→3；C₂→4；C₃→5；C₄→7；C₅→8；C₆→7；C₇→6；C₈→ 4}, the left interval (x) of the partition 3 corresponding to the smallest sub-partition ordinal number is taken_A1+3d) as the transverse minimum coordinate, and taking the 6 times interval span corresponding to the partition with the smallest sub-partition number and the largest sub-partition number as the transverse blocking span of the non-working area, so that the transverse interval of the non-working area is (x)_A1+2d，x_A1+8d)。

And 3, planning an unmanned automatic operation path, and determining the coordinates of the lifting and descending longitudinal positions of the farm tool.

FIG. 9 isSub-block and obstacle steering strategy diagrams in examples of embodiments of the invention. Referring to fig. 9, on the premise that the obstacle or the non-working area is not considered, when the span number of the sub-blocks is odd, and when the head of the sub-block is turned around and steered, the tractor runs on the land with the interval length of (q +1)/2 according to the turning angle; similarly, when the sub-block is turned around from the head to the side boundary, the tractor runs the block with the interval length of (q-1)/2 according to the turning angle. When the span number of the sub-blocks is even, the turning angle of the side of the ground boundary drives the land with the interval length of q/2, and the turning angle of the side of the ground boundary drives the land with the interval length of q/2-1. Sub-block B₁₆The degree of span of the sub-blocks is 6, and the turning sequence and direction thereof are { B }₁₁↑，B₁₄↓，B₁₂↑，B₁₅↓，B₁₃↑，B₁₆↓. In the same way, B₂₂：{B₂₂↑，B₂₁↓}；B₃₄：{B₃₁↑，B₃₃↓，B₃₂↑，B₃₄↓}；B₄₃：{B₄₂↑，B₄₁↓，B₄₃↑}；B₅₅：{B₅₃↓，B₅₁↑，B₅₄↓，B₅₂↑，B₅₅↓}。

When an obstacle or a non-operation area exists, in order to realize full-automatic path planning, secondary planning needs to be carried out on operation sub-blocks corresponding to the obstacle or the non-operation area to realize automatic obstacle avoidance. According to the processing result of the interval of the even-numbered edges of the position coordinates of each obstacle and the non-working area, the boundary of the obstacle or the non-working area is equal to the head boundary, the steering strategy is consistent with the above, and the specific implementation process can refer to fig. 9 and the corresponding description.

FIG. 10 is a schematic view of exemplary implement elevation and lowering longitudinal position coordinates in accordance with an embodiment of the present invention. Referring to fig. 10, each sub-block B is determined according to the tractor inherent deceleration safety distance D_pqLongitudinal position P for lowering farm tool in operation line_xq(x ═ a, b, c, d, e ═ q ═ 1,2, …,5,6) and implement elevation longitudinal position L_xq(x ═ a, b, c, d, e ═ q ═ 1,2, …,5, 6). In sub-blocks B₁₁And B₁₄Sub-blocks are taken as an example, and in the initial case, dragThe tractor enters an a1 operation line, and when the tail end farm tool is superposed with the ground of the operation line, the tractor is in a descending longitudinal position P of the sub-block farm tool_a1And sending a farm tool descending control signal at the position, descending the farm tool to a proper position, and starting the straight-ahead operation of the tractor. When the tractor moves straight to the end of the operation line with the distance a1, the tractor is at the lifting longitudinal position L of the sub-block farm tool_a1At the moment, the tractor starts to decelerate, and sends a farm implement lifting control signal when deceleration is finished, so that the farm implement is lifted to a certain height. The tractor starts to turn at a steering angle a₁In the direction of the steering angle₁₄. When the tractor body is parallel to the sub-block operation line, the tractor is in the sub-block B₁₄Straight-line operation acceleration point position P_a2When the farm tool is lowered to a proper position, the tractor starts to accelerate and move along the direction B₁₄And (5) performing straight-line operation. And by analogy, the tractor determines each sub-block B according to the automatic operation path planning_pqThe track entering sequence of the operation row, the descending longitudinal position of the farm tools of each sub-block operation row and the lifting longitudinal position of the farm tools. When an obstacle or a non-working area exists, according to the unmanned automatic path planning, a lowering longitudinal position and a lifting longitudinal position of the farm implement of the obstacle or the non-working area can be sequentially determined, and the specific implementation process can refer to fig. 10 and the corresponding description.

By way of example, the unmanned control method and system for the agricultural vehicle in the embodiment of the invention are an unmanned technical scheme which can not only give full play to the high precision and high reliability of the GPS navigation technology, but also can obtain accurate steering parameters, effectively solve the difficulty of automatic path planning in the unmanned process, and are efficient, stable and cost-saving.

Another embodiment of the present invention also provides a machine-readable storage medium having instructions stored thereon for causing a machine to perform the above-described method of controlling unmanned aerial vehicle of an agricultural vehicle. The machine-readable storage medium includes, but is not limited to, phase change Memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), Flash Memory (Flash Memory) or other Memory technology, compact disc read only Memory (CD-ROM), Digital Versatile Disks (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, and the like, which can store program code.

Another embodiment of the invention also provides an agricultural vehicle which comprises the agricultural vehicle unmanned control system. The agricultural vehicle is, for example, a tractor, and details of specific embodiments thereof are referred to above and will not be described herein again.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.

It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. The invention is not described in detail in order to avoid unnecessary repetition.

In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.

Claims

1. An agricultural vehicle unmanned control method, characterized by comprising:

acquiring closed farmland plot boundary data and discontinuous operation data acquired by a positioning system, wherein the discontinuous operation data comprises one or both of obstacle positioning data and non-operation area positioning data;

acquiring vehicle steering angle data; and

planning an unmanned automatic operation path according to the boundary data of the closed farmland plot, the discontinuous operation data and the vehicle steering angle data;

the closed farmland plot boundary data comprises a turning point position coordinate of a closed farmland plot boundary, the barrier positioning data comprises a barrier diagonal position coordinate, and the non-working area positioning data comprises a non-working area contour position coordinate; and is

Wherein the planning an unmanned automated work path according to the closed farmland parcel boundary data, the discontinuous work data, and the vehicle steering angle data comprises:

determining sub-blocks and sub-block spans according to the position coordinates of the turning points;

performing one or both of: judging the sub-blocks to which the diagonal position coordinates of the obstacle belong, determining a left interval of the sub-block to which the smallest abscissa in the diagonal position coordinates of the obstacle belongs as a transverse minimum coordinate, and determining the transverse blocking span of the obstacle as the smallest even-numbered multiple span capable of meeting the actual span requirement of the diagonal position coordinates of the obstacle; judging the sub-blocks to which the preselected contour position coordinates of the non-operation area belong, determining the left interval of the sub-block corresponding to the point with the minimum sub-block ordinal number as a transverse minimum coordinate, and determining the transverse blocking span of the non-operation area as the minimum even-numbered multiple span which can meet the actual span requirements of the point with the minimum and maximum sub-block ordinal numbers;

and planning an unmanned automatic operation path according to the sub-blocks, the sub-block spans, the transverse minimum coordinates and the transverse blocking spans corresponding to the obstacles and/or the non-operation areas and the vehicle steering angle data.

2. An agricultural vehicle unmanned control method of claim 1, wherein the planning an unmanned autonomous work path comprises:

when no obstacle and/or no operation area exists in the sub-block operation line, controlling the agricultural vehicle to steer according to different head-to-tail steering angles of the ground according to the parity of the sub-block span, wherein the steering driving distance is the interval length corresponding to the parity of the different sub-block spans; and

when an obstacle and/or a non-working area exists in the sub-block working line: equating an obstacle or non-working area boundary to a sub-block plot header boundary and fixing a steering angle to 90 ° to bypass the obstacle and/or non-working area; and taking the minimum even-number multiple interval span corresponding to the sub-block with the minimum ordinal number and the maximum ordinal number as the transverse blocking span, and controlling the agricultural vehicle to steer according to different steering angles at the head end and the tail end of the field according to the parity of the transverse blocking span, wherein the steering driving distance is the interval length corresponding to the parity of different transverse blocking spans.

3. An agricultural vehicle driverless control method as recited in claim 1 further comprising:

after the unmanned automatic operation path is planned, controlling the lifting and descending longitudinal position of the farm tool of each sub-block according to a preset safety distance before the farm vehicle reaches the ground, an obstacle or a non-operation area, wherein the controlling of the lifting and descending longitudinal position of the farm tool of each sub-block comprises one or both of the following steps:

for the sub-block operation line without obstacles or in a non-operation area, the lifting longitudinal position of the farm tool is the difference between the vertical coordinate of the ground head boundary point and the safety distance, and the descending longitudinal position of the farm tool is the position of the farm vehicle when the turning is finished and the farm vehicle enters the next sub-block and the vehicle body is parallel to the sub-block operation line; and/or

For a sub-block operation line with an obstacle or a non-operation area, the lifting longitudinal position of the farm tool is the difference between the longitudinal coordinate of the obstacle or the longitudinal coordinate of the non-operation area and the safety distance, and the descending longitudinal position of the farm tool is the position of the farm vehicle when the turning is completed and the farm vehicle enters the next sub-block and the vehicle body is parallel to the sub-block operation line.

4. An agricultural vehicle driverless control method as claimed in any one of claims 1 to 3, further comprising any one or more of:

comparing the vehicle steering angle data acquired by the steering sensor with the maximum value of the steering point angle of the planned unmanned automatic operation path, and judging that steering is finished when the vehicle steering angle data and the maximum value of the steering point angle of the planned unmanned automatic operation path are consistent;

comparing the real-time vehicle position with a deviation value of the planned unmanned automatic operation path, and if the deviation value exceeds a preset deviation threshold value, performing deviation compensation on the agricultural vehicle;

storing the closed farmland parcel boundary data, the obstacle positioning data, the non-working area positioning data and the vehicle steering angle data in real time; and

displaying the closed field plot boundary data, the obstacle positioning data, the non-work area positioning data, the vehicle steering angle data, and the planned unmanned automated work path.

5. A machine-readable storage medium having instructions stored thereon for causing a machine to perform the method of drone control of an agricultural vehicle of any one of claims 1 to 4.

6. An agricultural vehicle driverless control system, the agricultural vehicle driverless control system comprising:

the navigation function module comprises a positioning system and a non-continuous operation module, wherein the positioning system is used for acquiring boundary data of a closed farmland plot and non-continuous operation data, and the non-continuous operation data comprises one or both of obstacle positioning data and non-operation area positioning data;

the steering angle acquisition module is used for acquiring vehicle steering angle data; and

the path planning module is communicated with the navigation function module and the steering angle acquisition module and used for planning an unmanned automatic operation path according to the boundary data of the closed farmland plot, the discontinuous operation data and the vehicle steering angle data;

Wherein the path planning module comprises:

the sub-block determining submodule is used for determining sub-blocks and sub-block spans according to the position coordinates of the steering point;

a block processing sub-module for performing one or both of: judging the sub-blocks to which the diagonal position coordinates of the obstacle belong, determining a left interval of the sub-block to which the smallest abscissa in the diagonal position coordinates of the obstacle belongs as a transverse minimum coordinate, and determining the transverse blocking span of the obstacle as the smallest even-numbered multiple span capable of meeting the actual span requirement of the diagonal position coordinates of the obstacle; judging the sub-blocks to which the preselected contour position coordinates of the non-operation area belong, determining the left interval of the sub-block corresponding to the point with the minimum sub-block ordinal number as a transverse minimum coordinate, and determining the transverse blocking span of the non-operation area as the minimum even-numbered multiple span which can meet the actual span requirements of the point with the minimum and maximum sub-block ordinal numbers;

and the path planning processing sub-module is communicated with the sub-block determining sub-module and the block processing sub-module and is used for planning an unmanned automatic operation path according to the sub-blocks, the sub-block spans, the transverse minimum coordinates and the transverse blocking spans corresponding to the obstacles and/or the non-operation area and the vehicle steering angle data.

7. An agricultural vehicle unmanned control system according to claim 6, wherein the path planning processing sub-module for planning the unmanned autonomous working path comprises:

8. An agricultural vehicle driverless control system as recited in claim 6 further comprising:

the whole vehicle control module is used for controlling the lifting and descending longitudinal positions of the agricultural tools of each sub-block according to the preset safe distance before the agricultural vehicle reaches the ground, the obstacle or the non-operation area after the unmanned automatic operation path is planned;

wherein, whole car control module is used for controlling the agricultural implement of each sub-piecemeal to promote and descend vertical position and include:

9. An agricultural vehicle driverless control system according to any one of claims 6 to 8, further comprising any one or more of:

the angle feedback module is used for comparing the vehicle steering angle data acquired by the steering sensor with the maximum value of the steering point angle of the planned unmanned automatic operation path, and judging that the steering is finished when the vehicle steering angle data and the maximum value of the steering point angle of the planned unmanned automatic operation path are consistent;

the track deviation rectifying module is used for comparing the real-time vehicle position with a deviation value of the planned unmanned automatic operation path, and if the deviation value exceeds a preset deviation threshold value, performing deviation compensation on the agricultural vehicle;

the data storage module is used for storing the boundary data of the closed farmland plot, the obstacle positioning data, the non-operation area positioning data and the vehicle steering angle data in real time; and

and the state display module is used for displaying the closed farmland parcel boundary data, the obstacle positioning data, the non-operation area positioning data, the vehicle steering angle data and the planned unmanned automatic operation path.

10. An agricultural vehicle, characterized in that the agricultural vehicle comprises an unmanned vehicle control system according to any one of claims 6 to 9.